The overall objectives of the project are to investigate immunopathogenetic mechanisms in experimental and human renal diseases and to attempt to develop, in experimental models, ways in which the renal damage can be reduced through modification of the immune response. In particular, we will continue to study pathogenetic and structural aspects of cell mediated glomerular reactions, as produced by transfer of syngeneic lymphocytes from sensitized donors to recipient animals with glomerular bound or circulating antigens; investigate the antigens involved in Heymann (autologous immune complex) nephritis, and study the ways in which antiidiotype antibodies can suppress experimental anti TBM disease or Heymann nephritis. In addition, we will measure circulating T cell subsets in renal allograft recipients and in patients with various types of glomerulonephritis, through the use of monoclonal antibodies and flow cytometry, and study the nature of infiltrating cells in biopsies of renal allografts with monoclonal antibodies, using immunoperoxidase techniques.